Unable to loop/delete with QgsVectorLayer and dataProvider

Question

I have a csv file with the following columns:

table   geometry    field   type    typeName    len   precision

and my goal is to create a number of shp files programatically with PyQGIS.

My script stops after creating the first shp file.

Here's my code.

import sys
import re 
import csv
from PyQt4.QtCore import *
from PyQt4.QtGui import * 

reload(sys)  
sys.setdefaultencoding('utf8')
final_list = []

with open(r"D:\Users\Ravi_narayanan\Documents\shpgen.csv", "rU") as s:  
    reader_tables = csv.DictReader(s,delimiter=';')
    liste_tables = list(reader_tables)
    l_tables = [i['table'] for i in liste_tables]
    l_tables = set(l_tables)
    for table in l_tables:
        l1 = [line for line in liste_tables if line['table'] == table] 
        geometry = l1[1]['geometry']
        layer_mem = QgsVectorLayer(geometry+"?crs=epsg:2154",table,"memory")
        QgsVectorFileWriter.writeAsVectorFormat(layer_mem,r"D:\setupCAPFT2.00\{}.shp".format(table),"utf-8",None,"ESRI Shapefile",False)
        layer_path = "D:\{}.shp".format(table)
        shp = QgsVectorLayer(layer_path,table,'ogr')
        pr = shp.dataProvider()
        shp.startEditing()
        for field in l1:
            if field['type'] != 'Double':
                pr.addAttributes([QgsField(field['field'],getattr(QVariant,field['type']),field['typeName'],int(field['len']))])
            else:
                pr.addAttributes([QgsField(field['field'],getattr(QVariant,field['type']),field['typeName'],int(field['len']),int(field['precision']))])
        shp.updateFields()
        shp.commitChanges()
        shp.stopEditing()
        del layer_mem,shp,pr   

Answer 1

It was the

shp.stopEditing()

line that stop the script

Answer 2

I think you shouldn't use both dataProvider and an editing session at the same. It's either one or the other one.

The same script without the dataprovider, working only in an editing session:

shp = QgsVectorLayer(layer_path,table,'ogr')
shp.startEditing()
for field in l1:
    if field['type'] != 'Double':
        shp.addAttributes([QgsField(field['field'],getattr(QVariant,field['type']),field['typeName'],int(field['len']))])
    else:
        shp.addAttributes([QgsField(field['field'],getattr(QVariant,field['type']),field['typeName'],int(field['len']),int(field['precision']))])
shp.commitChanges()

or with the dataProvider without an editing session

shp = QgsVectorLayer(layer_path,table,'ogr')
pr = shp.dataProvider()
for field in l1:
    if field['type'] != 'Double':
        pr.addAttributes([QgsField(field['field'],getattr(QVariant,field['type']),field['typeName'],int(field['len']))])
    else:
        pr.addAttributes([QgsField(field['field'],getattr(QVariant,field['type']),field['typeName'],int(field['len']),int(field['precision']))])
shp.updateFields()

I would personally go for the first one.